Double-disk disk bit



July 13 1926.

G. c. DEAKINS DOUBLE DISK DISK BIT Filed Dec. 21, 1925 HTTOR/VEX cutter supporting pins. If the cutter Patented July 13, 1926.

GROVERC. DEAKINS, 0F ANAHEIM, CALIFORNIA.

DOUBLE-DISK DISK BIT.

Application filed December 21, 1925. Serial No. 76,645.

My invention relates to rotary disk bits such as are employed for drilling wells by the rotary system of drilling.

According to rotary practice, a bit is secured to the lower end of a drill pipe. This drill pipe extends through a rotary table of a rotary machine in a derrick of the well. A swivel head is attached to the upper end of the drill pipe, extending above the rotary table, and a traveling block is hooked thereto for supporting the drill pipe. A flexible hose extends from a stand pipe of a high pressure pump to the swivel head for supplying rotary mud to the rotary bit through the drill pipe. The rotary table rotates a drill pipe and the bit is revolved therewith, and digs away the bottom of the hole The rotary mud is supplied to the bit for carrying the cuttings thereof to the top of the well and for floating the drill pipe from engagement with the Walls of the well so that friction is reduced to a minimum.

The ordinary form of disk bit used in rotary drilling consists of, a body from which legs depend, cutter supporting pins which are supported by the legs and a pair of cutter disks, one being carried on each of said disks are set apart so that their contact with the walls of the hole causes them to rotate as desired, a core will form which will impair drilling, greatly slowing it up and often causing a crooked hole. On the other hand, if the disks are placed close together so that no core will form, the contact with the walls of the hole is not such as will rotate the cutter disks. Consequently, the disks will not rotate and the extensive cutting edges ained by reason of the operation of a disk 1s sacrificed.

It is an object of my invention to provide a rotary disk bit in which the disks will ro-' tate but will also cut away the core which forms as the hole is sunk.

It is another object of this invention to provide a rotary disk bit having loose cutters and tight cutters, each of which is placed on a cutter supporting pin, the loose cutter being rotatable thereon and the tight cutter being rigidly secured thereto, holding the loose cutter on the bit.

A further object of my invention is to provide a rotary disk bit having outer cutters and inner cutters, the inner cutters being in the form of nuts which are screwed onto the pins of the bit.

Other objects and advantages will be made evident'hereinafter.

Referring to the drawingsin which I illustrate a preferred form of my invention,

Fig. 1 is an elevational view of a bit enibodying my invention, a portion thereof being sectioned.

Fig. 2 is an elevational view of Fig. 1 taken as indicated by the arrow 2 of Fig. 1.

Fig. 3 is a cross section taken on the line 3-3 of Fig. 1. p Y I The form of my invention shown in the drawing provides a body 11 having a threaded pin 12.formed at the upper end thereof, by means of which the bit may be secured to a rotary drill pipe. Depending from the body 11 is a pair of legs 14. As clearly shown in Fig. 3, the legs 14 are offset on opposite sides of a center line AA which passes through the axis of the bit. The lower ends of the legs 14 are provided with openings 16 and openings 17, the openings 16 being of smaller diameter than the openings 17 and the openings 16 and 17 belng connected together. The openings 16 are provided with bushings 19 which have wear plates 20 formed integral therewith, these wear plates 20 being of radial extension and positioned in contact with the inner faces of the legs 14. The openings 17 are provided with bushings 22.

Rotatably carried by the legs 14 are cutter supporting members or pins 25. The

cutter supporting pins 25 have heads 26 which rest in the bushings 22 provided in the openings 17. Extending inward from the heads 26 of the cutter supporting members 25 are shaft portions 27 which extend through the bushings 19 of the openings 16. Placed on the shaft portions 27 of the cutter supporting members 25 are loose cutter disks 29. The inner ends of the shaft portions 27 are threaded as indicated at 30, and a short distance from'the ends of the pins grooves 31 are provided. Tight cutters 33 are secured on the inner ends of the cutter supporting members 25. These tight cutters 33 are provided in the form of nuts 34 which have threaded bores35 so that they may be screwed onto the threaded ends 30 of the shaft ortions 27. The tight cutters 33 are locke on the threaded portions 30 by means of set screws 37, the inner ends of which are adapted to rest in the grooves 31. Formed integrally with and surrounding the nut portions 34 are core cutters 39 which are part of the tight cutters 33.

\Vhen assembling the parts of my bit the cutter supporting members 25 are extended through the legs 14, after which the loose cutters 29 are placed thereon. The tight cutters 33 are then screwed into place, the cutter supporing members being held against rotation by means of a wrench which may be extended into the polygonal cavities 41 formed in the heads 26. After the tight cutters 33 have been screwed into proper positions, the set screws 37 are extended into the grooves 31, thus locking them securely in place. The heads 26 prevent the cutter supporting members 25 from moving inward beyond certain positions and prevent the tight cutters from engaging.

One of the features of this bit is that the loose cutters 29 may be offset a considerable distance and may be spread apart such a distance that the contact therewith with the wall of the hole being bored will tend to rotate them, thus taking advantage of the extensive cutting surface provided thereby.

It is possible to spread and olfset these disks because of the core cutters 39 which are placed in such a position that they will cut a core which forms as the hole is being bored. As shown best in Fig. 3, the adjacent cutting edges of these core cutters 39 are located very near to the axis of rotation B of the bit.

Another feature of the invention is the embodying of a core cutter and a nut in a unitary member. The loose cutters 29 rotate independently of the cutter supporting members 25 but the tightcutters 33 rotate with the cutter supporting members 25. It is necessary to have the cutter supporting members 25 rotatably supported by the legs 14 in order that the core cutters 29 may rotate and have advantage of their extensive cutting surface. The holes 16 and 17 provided in the legs 14 are hushed to take any wear. these bushings being replaceable. In the drawing I show the cutters 29 and 39 as being disk cutters. However, I do not wish to limit myself to disk cutters, since other rotatable cutters might be employed such as cone-shaped cutters.

I have found that the cutter supportin members may be locked from rotation and the bit will work successfully. In such a case the rigid cutters do not rotate and will not have as extensive cutting surfaces. I intend to file an application on this form of my invention and therefore desire to reserve ,all rights thereto.

-ter supporting pin; a nut rigidly secured to said cutter supporting pin, holding said loose cutter thereon; and a core cutter formed integral with said nut.

3. In a rotary bit the combination of: a body; a pair of legs depending from said body; cutter supporting pins carried by said legs; loose cutters rotatable on said cutter supporting pins; and tight cutters rigidly secured to said cutter supporting pins and holding said loose cutters thereon.

4. In a rotary bit the combination of: a body; a pair of legs depending from said body; a cutter supporting pins carried by said legs; loose cutters rotatable on said outter supporting pins; nuts rigidly secured to said cutter supporting pins and holding said loose cutters thereon; and core cutters formed integral with said nuts.

5. In a rota bit the combination of: a body; a pair 0 ofi'set legs depending from said body; cutter supporting pins carried by said legs and extending inward therefrom; loose cutters rotatable on said cutter supporting pins; and tight cutters rigidly secured to said cutter supporting pins and holding said loose cutters thereon.

6. In a rotary bit the combination of: a body; a pair of offset legs depending from said body; cutter supporting pins carried by said legs and extending inward therefrom; loose cutters rotatable on said cutters supporting pin's;-nuts rigidly secured to said cutter supporting pins and holding said loose'cutters thereon; and core cutters formed integral with said nuts.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 15th day of December, 1925.

' GROVER G. DEAKINS. 

